A retimer application system is provided, which includes a primary chip, a retimer, and a secondary chip. After first link training is completed, the retimer is configured to store, in a first storage area, an equalization parameter corresponding to each rate during the first link training, and data stored in the first storage area is not lost when the retimer performs a reset operation. The retimer is further configured to: receive a reset indication, and perform the reset operation according to the reset indication. The primary chip and the secondary chip are configured to perform second link training triggered by the reset indication. During the second link training, the retimer is further configured to: invoke the equalization parameter, and transparently transmit a training sequence in the second link training to the primary chip or the secondary chip based on the equalization parameter.